Sciencemadness Discussion Board

selective reduce nitroaromatics

cactusmae - 14-2-2012 at 07:38

I finially figured out the problem with my reduction with nitroaromatics with Iron and HCl. The problem is that I have a substitute with dihylogenated double bond CFBr-CF2Br. When I tried to reduce nitro group into amine with Iron, it is also dehylogenated CFBr-CF2Br and finally give a mixture. Any suggestion of reduce agent, which won't dehylogenated the compound?

Dr.Bob - 14-2-2012 at 10:37

Sodium dithionate might work. That is an interesting compound you've got.

UnintentionalChaos - 14-2-2012 at 14:19

That perhalogenated alkyl chain is going to be mighty reactive...when and if you can reduce the nitro group to an amine, I'd expect it to react immediately with the bromines on the sidechain. You could probably get away with reducing the nitro group on a nitrophenyltrifluoroethylene, but you wouldn't be able to brominate the product without serious issues.

cactusmae - 17-2-2012 at 08:05

Quote: Originally posted by Dr.Bob  
Sodium dithionate might work. That is an interesting compound you've got.

I tried sodium polysulfide once. It is not working. I am not sure why. Because without the CFBrCF2Br, it works fine with just perfluoroalkyl chain.

smuv - 17-2-2012 at 10:23

I recommend.hydrogenation w. adams catalyst in thf.

Organikum - 17-2-2012 at 14:08

You will have to find out the conditions under which reduction still takes place but your functional group stays unharmed.
There are several articles where the authors claim very selective reductions, which will do it for you only experiment can schow.

Attached are references for iron and tin and on the Zinin reaction with sulfides. There was another one with iron and CaCl2 which cannot find now, it was simply like it says and no HCl. Iron must be properly activated I suppose or not much will happen.

My personal bet would be on the SnCl2.

[Edited on 17-2-2012 by Organikum]

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